This Saturday, voters in Australia go to the polls in an election that's likely to result in a government shake-up. The country is facing a variety of economic problems. They include an end to Australia's mining boom and slowing demand from its main export market, China.

But as Stuart Cohen reports from Sydney, the hot-button issue of the election campaign isn't economics at all. It's illegal immigration.

ED HUSIC: I come for an audition, I get votes. That's awesome.

UNIDENTIFIED WOMAN: Oh.

HUSIC: Thank you very much.

STUART COHEN, BYLINE: Labor Party candidate Ed Husic is on the hustings, as Australians say, campaigning for re-election to his parliamentary seat in Sydney's sprawling western suburbs. Roughly one in 10 eligible voters live in this immigrant-filled part of Australia's largest city, so it's make-or-break territory for the two major parties hoping to run the country for the next three years.

Like voters in a lot of places these days, Husic's constituents are concerned about things like government spending and unemployment. But immigration comes up frequently as he makes the rounds of his electorate.

HUSIC: Look, out here, for example, I have people who've arrived from another part of the world and have done so on visitor visas or skilled visas or reunion, but have sought to get their own relatives here and can't because we run a pretty tough process of selecting people. And then they say: Well, how come I can't get my people here legitimately, but someone can arrive by boat?

COHEN: Tens of thousands of so-called boat people - often refugees from war-torn areas like Afghanistan, Iraq and Sri Lanka - have arrived on Australia's shores this year alone, usually coming by way of Indonesia in rickety and overcrowded fishing boats. For residents in Husic's electorate, like Eddie McCackley, the migrants are using up valuable social services and public housing.

EDDIE MCCACKLEY: We can't move out because them people are already in the new ones. It makes it harder for us to move into the new units and houses and that.

COHEN: For others, like Katherine Edgeworth and June Patosnik, there's a sense that the new arrivals who often pay thousands of dollars to so-called people smugglers for the journey are just economic migrants.

KATHERINE EDGEWORTH: Why should they come here? They're not really refugees. They're just people on a free ride getting in through the back door.

JUNE PATOSNIK: And if they have that much money to get on a boat, they're not a refugee.

COHEN: Even other immigrants like Helen, who chose not to give her last name, believe the boat people are getting preferential treatment.

HELEN: If you come to Australia legally, they give you a hard time. And the boat people, they come here easy. They can get everything. The money they spend in the boat people, why don't spend it here in Australia? There's still a lot of problem.

COHEN: Both of Australia's major parties have taken a get-tough policy with the refugees. Earlier this summer, the Labor Prime Minister Kevin Rudd drew condemnation from human rights groups when he announced a plan to send anyone arriving by boat to Australia's northern neighbor of Papua New Guinea for resettlement and prevent them from ever gaining residency in Australia. The opposition leader, Tony Abbott, has gone a step further, promising to tow the boats back to Indonesia.

PETER HARTCHER: And there has been a race to the bottom in trying to vilify the refugees in the process of trying to stop them.

COHEN: Peter Hartcher is political editor for the Sydney Morning Herald. He says despite the perceived flood of refugees headed for Australia's shores, voters here have very little to worry about.

HARTCHER: What are perceived as the big Australian problems are actually pretty modest. The budget deficit is 1 percent of GDP. There's very, very little federal government debt. The flow of refugees arriving in boats is 20 to 30,000 a year. These are, by international standards, problems that, you know, other countries would love to have. But here they're regarded as major problems.

COHEN: Polls show Australia's conservatives, led by Tony Abbott, are likely to win a majority, ending six years of Labor Party rule. Abbott has promised a raft of major changes, including an end to the country's tax on greenhouse gas emissions.

TONY ABBOTT: There's almost nothing at all wrong with Australia right now that wouldn't be improved by a change of government. We will scrap the carbon tax. We will get the budget back into the black. And we will stop the boats.

COHEN: Whichever party wins on Saturday will also have to deal with an economy that, for the first time since the start of the global financial crisis, is showing signs of slowing down as demand from China for Australia's rich mineral resources is starting to wane.